Sage Therapeutics declined a 30% premium acquisition offer from Biogen CEO Chris Viehbacher after FDA setbacks for its depression drug Zurzuvae and pipeline failures. Following mixed regulatory outcomes, Sage sought alternative financing, engaging 43 parties before agreeing to an acquisition by Supernus Pharma for up to $795 million centered on Zurzuvae's approved post-partum depression indication. The breakup highlights strategic shifts in small biotech partnerships post-FDA review.